As mentioned previously, this message indicates a problem with the structured grid's topology. Most often the cause is one of these:

You have coincident connectors on the edges of adjacent faces. Use the Merge command to resolve this.

The faces do not form a computationally IxJxK block. Check the dimensions of your domains.

Thank you for your reply, John .
I'm not really understand the second reason you listed there. I want to creat a structure block around a wing, and two domains have different IxJ. In one domain, the IxJ is 206x77 and in the other domain , 77x206. Is that right?

As mentioned previously, this message indicates a problem with the structured grid's topology. Most often the cause is one of these:

You have coincident connectors on the edges of adjacent faces. Use the Merge command to resolve this.

The faces do not form a computationally IxJxK block. Check the dimensions of your domains.

Hi, John.
As you listed, the reason why I couldn't creat the block is that there are coincident connectors on the edges of adjacent faces. I checked the connectors one by one to find if there are coincident connectors on the edges of adjacent faces or not. It's not efficiency, so is it another way to check the connectors?
Best regards!
Json Shih

Pointwise has the capability to find overlapping connectors and nodes using the Merge... option in the Grid menu. In this panel you can set a tolerance and Pointwise will find adjacent connectors and nodes that lie within this specified tolerance. Once highlighted, you can opt to merge them. Alternatively, you can simply replace one with the other by selecting the first, and then the second entity. You can read more about this panel in the User Manual. This feature is also demonstrated in one of the videos of our #TutorialTuesday video series. The video can be viewed here.

Pointwise has the capability to find overlapping connectors and nodes using the Merge... option in the Grid menu. In this panel you can set a tolerance and Pointwise will find adjacent connectors and nodes that lie within this specified tolerance. Once highlighted, you can opt to merge them. Alternatively, you can simply replace one with the other by selecting the first, and then the second entity. You can read more about this panel in the User Manual. This feature is also demonstrated in one of the videos of our #TutorialTuesday video series. The video can be viewed here.

Thank you for your reply, Zach.
For some technical reason, I can't see the video on youtube, but your answer do help me a lot!
Jason